my thought is this: I think his chew toy needs to as obvious as rubber bone... why? Because right now, there's nothing to tell the audience that the purple bird is the beloved possession of the dog - there's no obvious connection there. If it was a rubber bone, however, we'd understand the connection right away. For me, there's still something not quite right in the set-up - that the bone has been accidentally sucked out into space - feels like we need a bit more staging of that idea in the set up to kick everything off in an idiot-proof way...